1. Field of the Invention
This invention relates to compound gear arrangements, and in particular to such an arrangement when intended for use as a geared hinge for an aircraft.
2. Description of the Prior Art
It is known, for example, from U.S. Pat. No. 3,008,355, to provide a geared hinge device which comprises an epicyclic gear train by means of which rotation of an axial input shaft causes rotation between adjacent annular members. As shown in the aforesaid patent it is also common practice to provide a plurality of identical axially aligned epicyclic gear trains each of which is driven by the same axial input drive shaft. This arrangement is intended to ensure that shearing of a drive element in one of the gear trains nevertheless allows the hinge to continue operating with the remaining one or more intact trains.
It is a disadvantage of such known arrangements that since gear trains which comprise the arrangement as a whole may have substantial length, when the arrangement is used, for example, as a geared hinge for a lift control surface on an aircraft wing, flexing of the wing, or the lift control surface, may result in stresses or misalignment of the gear train components.